Flotation machine



Patented CHARLES E. RORK AND AUGUST SANDBERG, OF DOUGLAS, ARIZONA, ASSIGNORS, BY

DIRECT MESNE ASSIGNMENTS, TO WILL A. BUTCHART, 0F DENVER, 0010- EA'DO.

,FLOTATION EACEINE.

Application filed June 18, 1917. Serial No. 174,583.

To all whom it may concern:

Be it known that we, CHARLES E. Born, a citizen of the United States, and Aoens'r SANDBERG, a subject of the King of Sweden, residing at Don las, in the county of Cochise and State of rizona, have invented certain new and useful Improvements in F10 tation Machines, of which the following is a s ecification.

ur invention relates to new and useful improvements in flotation machines or separators of the type employed for separating minerals from a pulp of the gangue material of their ores, one of the objects of our invention being the provision of a flotation separator of novel construction having a single agitating chamber with an agitator therein co-operating with a flotation chamber that discharges over an overflow lip into ,a longitudinally disposed launder.

Another object of our invention is to provide means for passing the settled gangue from the settling chamber back to the agitation chamber.

Another object which we have in view is the. arrangement of walls and bafiles be tween the agitation chamber and settling chamber of such a character that the pulp is elevated to a minimum height only in order to deliver it from the agitation chamber into the settling chamber, the impeller or agitator running under shot with respect to the point of delivery of the pulp so as to raise it and discharge it over the relatively low partition wall between the chambers.

With these and other objects in view, our invention will be more fully described, illustrated in the accompanying drawing, and then specifically pointed Jout in 'the claims which are attached to and form a part of our application.

The figure of the drawing is a transverse sectional view of a machine constructed in accordance with our invention.

Our improved flotation machine,-briefly described, consists of a relatively long agitating chamber into which the pulp IS introduced through an inlet atone end of said chamber, a settling chamber arranged at one side of said agitating chamber and separated therefrom by a vertically-disposed partition that extends longitudinally of the machine and a rotable agitating device in the said agitating chamber which turns in such a direction that the pulp in said agitating chamber will be moved towards the vertical partition between said chambers and then lifted or moved upwardly in a substantially vertical path and discharged overv the upper ed e of said partition into the settling cham er. The settling chamber is preferably divided into a number of separate and distinct compartments, each of which is provided at its lower end with a discharge passageway that communicates with the agitating chamber, and separate and distinct valves are preferably employed for controlling the discharge passageways leading from the individual compartments of the settling chamber to the agitating chamber. It is immaterial, so far as our broad idea is concerned, what particular kind of agitating device is used in the agis tating chamber for agitating the pulp and feeding it upwardly over the partition between the agltating chamber and the settling chamber, but we prefer to use a horizontallydisposed device of substantiallysquirrel cage form, hereinafter referred to as an impeller, which is so constructed that it will draw air into the agitating chamber and whip or beat said air into the pulp so as to partially aerate the pulp, which device forms the subject-matter of our pending application for patent 'Serial .No. 433,867, filed December 29, 1920. Means is also preferably provided for enabling additional air or other suitable fluid to be introduced into the pulp after the pulp has escaped from the agitating chamber so as to complete the aeration of the pulp, the means herein illustrated for this pur ose consisting of a pressure chamber provided with a porous or perforated wall over which the pulp passes in traveling from the agitating chamber into the settling chamber. The action in the settling chamber is substantially the same as in other machines of this general type, namely, the metallic particles of the ore are carried upwardly to the surface of the liquid in the settling ways leading from the individual compartments of the settling chamber and the rotary movement of the agitating device in the agitating chamber feeds the pulp longitudinally of the machine towards a discharge opening or outlet pipe located at the opposite end of the machine from that at which the pulp enters, the various elements or parts of the machine being so arranged that the pulp will pass from the agitating chamber HitO the first compartment of the settling chamber, thence back into the agi tating chamber, and so on through the various compartments of the settling chamber. Means is arranged in the agitating chamber for preventing the pulp that flows from the settling chamber back into the agitating chamber; from being subjected to counter currents or to pressure produced by the rotary movement of the impeller, and means is also provided for reventing the pulp from adhering to the impeller and being carried completely around the agitating chamber by the impeller. In the preferred form of our invention, as herein shown, the machine consistsof a substantially rectangular-shaped body formed of planking and including a bottom wall 10, front wall 11, back wall 12, and end walls. The bottom wall is supported upon suitable timbers or blocks 14 and the joints between the planks forming all of the Walls are filleted, as indicated at 15. The main portion of the bottom wall is horizontally disposed, but adjacent the rear wall is provided with an upwardly-inclined section 16. This section is supported by abutment blocks 17 mounted upon the timbers 14: and held against longitudinal movement by keys 18 and against vertical movement by tie bolts 19 and nuts 20. The body also includes a fixed cover section 21 of plank which extends throughout the length of the body and which overlies the front portion ofthe body leaving the back portion open, save for a supplemental cover section 22 which is connected to the fixed cover section by hinges 23. The front edge of the cover section 21 projects beyond the front wall of the body and the entire cover section 21 is braced at suitable intervals by transversely extending binding straps 24 secured by bolts 25. Preferably, those leaves of the hinges which are connected to the cover section 21 are sunk into the cover so that the straps may overlap them, under which circumstances certain of the strap securing bolts will also serve to secure the hinges.

The front wall is braced by angle plates 25 secured to the extended ends of the timbers 14. their lower ends passed through the extended ends of brace timbers 35 which reinforce the bottom of the body and secured by nuts 36. i

The impeller shaft 48 extends horizon- Furthermore, tie rods 34 have tally and parallel to the front wall of the body and is located substantially midway between the bottom of the body and the cover and at approximately the same distance from the front wall. Mounted upon this shaft, at suitable intervals, and secured thereby by keys, are a plurality of spiders 58 of metal, each having an annular peripheral flange 59 notched to provide seats 60 for a plurality of peripherally spaced impeller blades 61, preferably formed of wood. These blades, as well as the seats, are slotted to receive locking keys '62 by means of which the blades are detachably secured to the spiders. It should be noted that these blades extend from the spiders at an angle to the radial so as to in effect form shallow lifting buckets when the impeller is driven in the direction indicated by the arrow, which will lift material towards the center of the body, the blades at their ends terminating just short of the end walls of the body.

A longitudinal partition wall 64 extends throughout the length of the machine, dividing it into an agitation chamber 65 and a settling chamber 66. The upper end of this partition wall extends somewhat above the central portion of the impeller, while its lower end is spaced above the bottom of the machine. This partition is spaced from the impeller a distance substantially equal to the space between the impeller and the front wall of themachine and at its lower edge rests upon a horizontally-disposed false bottom section 67 which is spaced above the true bottom 10, and which, at one edge, is spaced slightly from the lower portion of the inclined section 16 of the bottom wall to provide a restricted passage 68. A plurality of transverse partitions or baffles 69 extend across the settling chamber 66 at spaced intervals, thus dividing said chamber into a number of separate and distinct compartments, the upper edges of said partitions being spaced below the overflow lip 70 formed by the upper edge of the rear wall 12 of the settling chamber, which is lower than the remaining walls of the machine, and these partitions have extensions 71 which support the false bottom section 67 and which, with the false bottom and true bottom, provide a plurality of passages 72 leading from the continuous passage 68 to the lower portion of the agitation chamber 65. A depending, longitudinally-extendin baffle wall 73 is supported in paralle spaced relation to the wall 64 with its lower free edge spaced somewhat below the upper edge of thebaflles 69, which, in turn, lie below the upper edge of the partition wall 64, save for the space between the overlapping portions ofthe walls 64 and 73 where the transverse bullies or partitions 69 are extended to lie flush with the upper edge of the wall 64, This bafile wall 73 is supported byfa plurality of strap bolts 74,

the shanks of which are passed through the hinged section 22 of the cover and through the inner ends of brackets 75 and which receive nuts 76. These brackets are further fastened by bolts 77 and nuts 78 and at their free ends project beyond the edge of the cover and have sleeves 79 which are disposed vertically above the passages 68 and which slidably receive the threaded upper ends of valve supporting rods 80, such ends being provided with wing adjustin nuts "81 by means of which the rods may e raised or lowered through the sleeves. Preferably, two of' these brackets are disposed over each section of the settling chamber 66 and the lower ends of the rods 80 are passed through the walls of tubularcylindrical gate valves 82, nuts 83 serving to clamp the gate valves to the lower ends of the rods. Each gate valve extends throughout the length of its section or compartment of the settling chamber and has its ends slidably mounted between spaced guides 84 secured either to the end walls of the body or to the bafile walls 69, as the case may be. As shown in the drawing, these gate valves are so proportioned that in lowered position they may completely close the passages 68.

Disposed within the agitation chamber 65 is a false bottom section 86 which is arc'uate in cross section. This false bottom corresponds in curvature to the curvature of the impeller, its upper edge being secured to the intermediate portion of the front wall of the machine and its opposite edge projecting slightly beyond the vertical plane of the impeller shaft. Walls 87, extending transversely, support this false bottom 86 at suitable intervals, one of these walls being disposed directly at the free end of the false bottom and a longitudinal wall 88 also supports the false bottom adjacent its free edge and with the last mentioned of the walls 87 serves to completely enclose the space between the false bottom and true bottom of the machine, so that none of the contents of the machine may escape to that space.

Partition wall sections or baflles 89 extend from the wall 88 in alignment with the partitions or baflles 71 to a point slightly spaced from such partitions or bafies and support a longitudinal bafile block 90 substantially triangular in cross section with its inclined face op osed to the impeller. A. corres onding ba e block 91 extends longitudinally of the agitation chamber, engaging against the cover and having its inclined face opposed to and spaced but a slight distance from the outer edges of the impeller blades. That face of this latter battle block, which is adjacent the heme 73, is channeled longitudinally to receive a longitudinal tie rod 92 and is covered with rubber belting 93 settling chamber.

Extending longitudinally of each section of the settling chamber 66 are inclined-deflector plates or walls 95 which rest at their upper edges against the intermediate ortion of the partition walls 64 and at t eir lower edges upon the free edge of the false bottom section 67., that is, adjacent the gate valves 82. This false bottom section 67, partition wall 64, and deflector walls 95 extend throughout the entire length of the machine and the deflector wall 95 is preferably formed of some porous material through which air may pass in fine streams. If this is the case, one end of an air supply pipe 96 is led into that end wall of the machine to communicate with the space between the false bottom section 67, partition wall 64 and deflector plates 95. Furthermore, under these circumstances, the partition or bafile walls 69 will be formed with openings beneath the deflector plates so as to provide a continuous air chamber from one end of the machine to the other.

Built along the back wall of the machine at a working level, near the upper edge of the partition wall 64, and pulp is fed through an inlet pipe at the proper rate and discharged into the inlet end of the agitation chamber in which the impeller is being rotated at the roper speed in the direction indicated by t e arrow. Under these circumstances, the pulp is lifted by the blades of the impeller and discharged over the upper edge of the artition wall or baffle 64 and settles throng the space between this wall and the bafie 73 into the first section of the settling chamber or spitzkasten. The

action of the impeller not only serves to agitate the pulp and discharge it into the settling chamber, but also acts as a blower to draw additional air into the agitating chamber through openings in the ends of same. Furthermore, if a porous deflector wall 95 is employed, the air supplied through the pipe 96 will be forced through the ulp, as it passes over the deflector wall. nder these circumstances, a certain proportion of the mineral particles contained in the pulp will become coated with minute air bubbles, so that they will rise to the surface of the flotation liquid and form a froth which will flow from the discharge lip into the launder. The remainder of the pulp will settle to the bottom of the spitzkasten and will pass through the gate valves of that section of the spitzkasten into which it has been discharged and through the adjacent passage 72 back to the agitation chamber where it will be aerated, raised and discharged by the the settling chamber and so on throughout the entire length of the machine. Obviously, in each section of the settling chamber a further proportion of the mineral contents of the pulp will be floated 0d so that by properly regulating the rate of flow of the pulp and by providing a sufiicient number of settling chamber sections for the type of pulp being treated, all mineral matter may be removed. The baliie block 91 prevents the pulp from being carried completely around the agitation chamber by the impeller, while the battle block 90 prevents pressure, due to the action of the impeller from acting against pulp entering the agitation chamber through the passages 72. I

Although we have illustrated and described our invention in all its details of construction, it will, of course, be understood that'we do not wish to limit ourselves to such details, but reserve the right to make any changes, within the scope of the appended claims, without in the slightest degree departing from the spirit of our invention.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

menace tating device in said chamber, a discharge passageway leading upwardly from the bottom of the agitatin chamber to an outlet opening adjacent the aorizontal center of the agitating device, said discharge passageway and outlet opening being so disposed with relation to the agitating device that the liquid in said chamber will be lifted by the rapid rotation of said agitating device and discharged laterally through said outlet opening in a direction opposite to, that of the rotation of said agitating device,

2. In a machine of the character described, an agitating chamber that is adapted to receive pulp, a settling chamber arranged so that pulp can pass from said agitating chamber into the upper end of said settling chamber, a discharge passageway leading from the lower end of said settling chamber through which pulp can pass back into said agitating chamber, a rotatable device in said agitating chamber which revolves in such a direction that it tends to move the pulp in said agitating chamber towards the discharge passageway through which the pulp returns to the agitating chamber, and a bafile arranged between said rotatable device and the opening of said discharge passageway through which the pulp returns to the agitating chamber.

3. In a machine of the character described, an agitating chamber adapted to receive pulp, a settling chamber into which the pulp is discharged from said agitating chamber, a discharge passageway leading from the lower end of said settling chamber through which pulp is conducted back into said agi' tating chamber, a rotatable device in said agitating chamber for lifting the pulp therein and causing it to escape into the settling chamber, a bafiie arranged in said agitating chamber between said rotatable device and the opening of the discharge passageway through which the pulp returns to the agitating chamber, and means arranged in said agitating chamber above the axis of said rotatable device for preventing the pulp from being carried completely around said agitating chamber by said rotatable device,

In testimony whereof We aliix our signatures.

CHARLES E. RORK. [n a] AUGUST SANDBERG, [1 s.] 

